Catheter apparatus

ABSTRACT

A proximal terminal end of a proximal section of a catheter, preferably tapered, defines a perimeter of an opening into a lumen of the catheter and includes an exposed sealing area. A sealing assembly, that may be removed from the catheter, includes a relatively soft part and a relatively rigid part, wherein the exposed sealing area is formed by the soft part, and the relatively rigid part may include an attachment feature for removable connection of the assembly to the catheter. The lumen of the catheter, within the proximal section, may include a seal zone portion, which preferably includes a slit segment intersecting a funnel-like segment of a bore. The catheter proximal section may further include a feature for interlocking engagement with an accessory tool.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/848,054, filed Jul. 30, 2010 entitled “CATHETER APPARATUS”, hereinincorporated by reference in its entirety.

The present application is related to three co-pending andconcurrently-filed applications, all of which are hereby incorporated byreference, in their entireties, and which have the following titles anddocket numbers: MEDICAL DELIVERY SYSTEMS AND APPARATUS—P0036991.00;TOOLS AND METHODS RELATED TO CATHETER DELIVERY—P0036919.00; and SEALINGFOR MEDICAL DEVICES/INSTRUMENTS—P0036566.00.

TECHNICAL FIELD

The present invention pertains to apparatus for positioning/deliveringmedical devices/instruments within a body of a patient.

BACKGROUND

Various types of catheters and associated methods for the delivery ofmedical devices/instruments to target sites within a patient's body areknown in the art. A properly positioned catheter can provide aconvenient conduit for an operator/clinician to pass an elongate medicaldevice, such as a medical electrical lead, into the body in order todeliver a site specific therapy from the device. However, the task ofpreventing excessive leakage/backflow of bodily fluids, for example,blood, and/or other procedure-related fluids out from a positionedcatheter can, at times, somewhat complicate catheter deliveryprocedures.

With reference to FIG. 1, a portion of a catheter delivery system, whichis known in the art, is shown. FIG. 1 illustrates the system including acatheter 800, a sealing assembly 820, a syringe 810, a relativelysmaller diameter guide wire 200, a relatively larger diameter guide wire200′ and an insertion accessory tool 822, for example, to assist ininserting devices/instruments, such as guide wires 200/200′, a medicalelectrical lead and a sub-selecting catheter, into catheter 800. Anexample of the illustrated catheter 800 is the Attain Command® Catheter,available from Medtronic, Inc., and examples of the illustrated guidewires 200/200′ can be any of the many suitable guide wires known tothose skilled in the art; an example of the sealing assembly 820 andassociated insertion tool 822 is the SafeSheath® Sealing Adapter andassociated Transvalvular Insertion Tool, available from PressureProducts. According to FIG. 1, sealing assembly 820 is connected tocatheter 800 by inserting a distal end 823 of assembly 820 into a hub811 of catheter 800, and, once connected, a valve/seal member (forexample, like that described in U.S. Pat. Nos. 5,125,904, 5,312,355 and5,409,463), which is located within a body 825 of assembly 820, inproximity to a proximal end 824 thereof, both seals off a lumen ofcatheter 800 and provides a passageway into the lumen. This passageway,into the lumen of catheter 800, is intended to allow passage of amedical device, for example, a medical electrical lead, therethrough, sothat the operator may deliver the device, through the lumen of catheter800, to a target site, within a body of a patient. The valve/seal memberof assembly 820 is designed to seal around the device as it passestherethrough and thereby prevent an excessive volume of bodily fluidsfrom leaking out from proximal end 824, and the design thereof is suchthat tool 822 is typically required to provide passage therethrough forthe device.

The valve/seal member may further seal about a dilator device (notshown), which facilitates introduction of catheter 800 into thepatient's venous system via a venous access site. Larger diameter guidewire 200′, for example, having a 0.035 inch diameter, may be used togain initial access and the dilator, having a uniform inner diameterprovides a passageway through the valve/seal member as the operatorintroduces catheter 800 over guide wire 200′, in order to positiondistal end 89 of catheter within the venous system, according to methodsknown in the art, prior to delivering the medical device through thelumen. Smaller diameter guide wire 200, for example, having a diameterof approximately 0.014 inch, may be used to facilitate the delivery ofthe device. Upon removal of the dilator and the larger diameter guidewire 200′, smaller diameter guide wire 200 may be loaded into the lumenof catheter 800 from proximal end 824 of sealing assembly 820, whereininsertion tool 822 may be necessary to facilitate insertion of a distaltip 209 of guide wire 200, which is typically somewhat floppy anddeformable, through the valve/seal member of assembly 820. Tool 822 is adisposable tubular member that is easily peeled away from around loadedguide wire 200, by pulling apart ends 802. Alternately, if a guide wireis not employed, tool 822 may assist in inserting a medical device, suchas an electrical lead, into the lumen of catheter 800, after which, tool822 may be peeled away from around the inserted device.

FIG. 1 further illustrates sealing assembly 820 including a side tubingport 826 extending to a stopcock 827, which is coupled to syringe 810;tubing port 826 provides a passageway for the injection of a fluid fromsyringe 810 into the lumen of catheter 800, downstream or distal of thevalve/seal member of valve assembly 820. The fluid may be a saline flushor a radiopaque contrast agent that is useful for visualizing anatomy,for example, a venous anatomy on fluoroscopy, which is downstream ofdistal end 89 of catheter 800, and thereby facilitate the positioning ofdistal end 89, guidewire 200 and/or the medical device at, or inproximity to a target site. Thus, the valve/seal member of assembly 820must also prevent backflow of the fluid injected from syringe 810 aroundboth guide wire 200 and the medical device, which are either together orindividually inserted through the valve/seal member.

Once the medical device is delivered to the target site through catheter800, if the medical device is to remain implanted within the body at thesite, catheter 800 is removed out from the body and from around themedical device. FIG. 1 shows a dashed line extending along a length ofsealing assembly 820 to represent a weakened section along which sealingassembly 820 may be split apart for removal from around the implantedmedical device body. Splitting apart sealing assembly 820 is necessarywhen a proximal end of the implanted medical device will not fit throughthe valve/seal member of the assembly. Other sealing assemblies known inthe art, for example, the Toughy-borst type, are configured to allow theoperator to expand and contract the corresponding valve/seal member suchthat in the contracted state, the valve/seal member seals around adevice inserted therethrough, and in the expanded state the valve/sealmember is sufficiently opened so that a larger proximal end of thedevice will fit through the valve/seal member. Having the ability toalternately expand and contract the valve/seal member can alternatelyfacilitate the movement of devices and guide wires through thevalve/seal member, when expanded, and provide better sealing, whencontracted, but also requires additional manipulations from theoperator, which can make the catheter delivery procedure a bit moretedious. Toughy-borst type sealing assemblies may also include a tubingport connected thereto, similar to that described above, so that fluidmay be injected through catheter 800 downstream of the valve memberthereof.

Although the above-described valve assemblies enable catheter deliveryprocedures, there is still a need for improved apparatus and methodsthat can prevent excessive leakage/backflow and facilitate simplercatheter delivery procedures.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are illustrative of particular exemplaryembodiments and therefore do not limit the scope of the invention. Thedrawings are not to scale (unless so stated) and are intended for use inconjunction with the explanations in the following detailed description.Embodiments of the present disclosure will hereinafter be described inconjunction with the appended drawings, wherein like numerals denotelike elements.

FIG. 1 is a plan view of a portion of a prior art catheter deliverysystem.

FIG. 2A is plan view of a catheter, according to some embodiments of thepresent invention.

FIGS. 2B-C are schematics depicting some methods facilitated by aproximal section of the catheter shown in FIG. 2A.

FIG. 3A is an exploded perspective view of the proximal section of thecatheter of FIG. 2A, according to some embodiments of the presentinvention.

FIG. 3B is a perspective view of a sealing assembly, according to someembodiments.

FIG. 3C is an exploded perspective view of the sealing assembly,according to some embodiments.

FIGS. 4A-B are end views of the sealing assembly within the catheter ofFIG. 2A, according to some embodiments.

FIG. 5A is a longitudinal cross-section view through the sealingassembly within the catheter of FIG. 2A, according to some embodiments.

FIGS. 5B-C are schematic series of radial sections at various depthsalong a seal zone portion of a lumen of the sealing assembly of FIGS.4A-B and 5A.

FIG. 5D is a schematic side view along the seal zone portion of thelumen, according to some embodiments.

FIG. 6 is a perspective view of the proximal section of the catheteralong with a slitter tool, according to some embodiments.

FIG. 7A is a plan view of the proximal section of the catheter alongwith a syringe adapter tool and a syringe, according to someembodiments.

FIG. 7B is a perspective view of the proximal section with the syringeadapter tool and the syringe connected thereto.

FIG. 7C is a longitudinal cross-section view of the proximal sectionshown in FIG. 7B, according to some embodiments.

FIG. 7D is a plan view of the syringe adapter tool, according to someembodiments.

FIG. 8A is a perspective view of an alternate embodiment of a syringeadapter tool.

FIG. 8B is an enlarged perspective view of the syringe adapter tool ofFIG. 8A engaged with the proximal section of the catheter.

FIG. 9 is a plan view of a catheter delivery system, according to someembodiments of the present invention.

DETAILED DESCRIPTION

The following detailed description is exemplary in nature and is notintended to limit the scope, applicability, or configuration ofembodiments disclosed herein. Rather, the following description providespractical illustrations for implementing exemplary embodiments. Examplesof constructions, materials, dimensions, and manufacturing processes areprovided for selected elements, and all other elements employ that whichis known to those of skill in the field of the disclosure. Those skilledin the art will recognize that many of the examples provided havesuitable alternatives that can be utilized.

FIG. 2A is plan view of a catheter 100, according to some embodiments ofthe present invention. FIG. 2A illustrates catheter 100 extending from aproximal section 11 thereof to a distal end 19 thereof; a lumen 101 ofcatheter 100 (shown with dashed lines) extends distally to distal end 19from a proximal opening 31 thereof, which has a perimeter defined by aproximal terminal end 113 of proximal section 11. According to theillustrated embodiment, proximal terminal end 113 has a tapered profileand preferably includes an exposed sealing area 123, which is mainlyexposed by virtue of the tapered profile. Exposed sealing area 123 ispreferably formed from a relatively soft and resilient material, forexample, a liquid silicone rubber (LSR) material or a thermoplasticelastomer (TPE) material, as compared to a material that forms arelatively rigid sidewall 111 of proximal section 11, for example, apolyether block amide such as Pebax®, which is a material commonly usedin the construction of catheter sidewalls, or a polyolefin such asPro-fax. It should be noted that, although preferred, some alternateembodiments of proximal section 11 need not include the tapered profileat proximal terminal end 113, or exposed sealing area 123.

FIG. 2A further illustrates lumen 101 including a main portion 101 m, aseal zone portion 101 s and a proximal port portion 101 p, wherein sealzone portion 101 s forms a passageway (i.e. having a diameter) that issmaller in size than that of each of main portion 101 m and proximalopening 31, in order to provide a sealing interface with an elongatebody of a medical instrument/device that is passed through lumen 101.Main portion 101 m is shown extending distally from seal zone portion101 s toward distal end 19 of catheter 100; and proximal port portion101 p is shown extending distally from proximal opening 31 to seal zoneportion 101 s. Proximal port portion 101 p is preferably sized toreceive a standard tapered tip of a syringe, for example, having a luertaper known to those skilled in the art, either in a luer-lockconfiguration (syringe 810, FIG. 1, and syringe 710, FIG. 7A) or in aluer slip fit configuration (syringe 210, FIG. 2C). Thus, according toan exemplary embodiment, a size of proximal opening 31 and proximal portportion 101 p in proximity to proximal opening 31 will accommodateinsertion therein of a syringe tip having a maximum diameter of up toapproximately 0.16 inch. Seal zone portion 101 s is preferably formedfrom a relatively soft and resilient material, for example, an LSR orTPE, that will elastically stretch and compress in order to provide aninterference fit for sealing around larger diameter instruments/devices.According to some embodiments, which will be described in greater detailbelow, a relatively soft part of proximal section 11 forms both sealzone portion 101 s and exposed sealing area 123 and extends therebetweento define a portion of a perimeter of proximal port portion 101 p.

An initial diameter of seal zone portion 101 s may be required to expandas little as approximately 1% and up to approximately 1000% in order toaccommodate passage therethrough of a variety of instruments/devicesthat range in outer diameter from approximately 0.010 inch toapproximately 0.12 inch. Some LSR and TPE materials are known to exhibitsuch a range of elongation, for example, Shin-Etsu KE-2090-10 LSR (980%)and Dynalloy™ OBC 8000-T05 (1800%), but a material selection for sealzone portion 101 s could be rather limited by this requirement. If sealzone portion 101 s is sized to particularly accommodate passage ofinstruments/devices that have relatively large outer diameters, forexample, medical electrical leads that have diameters ranging fromapproximately 0.04 inch to approximately 0.09 inch, seal zone portion101 s may have a diameter that is too large to adequately seal around asmaller device/instrument, such as relatively smaller diameter guidewire 200, which may have an outer diameter of approximately 0.01 inch,or relatively larger diameter guide wire 200′, which may have an outerdiameter of approximately 0.03 inch; or, if seal zone portion 101 s issized to particularly accommodate passage of the relatively smallerinstruments/devices, like aforementioned wires 200/200′, then, unlessthe material of seal zone portion 101 s has the necessary elongationproperties, insertion of a device/instrument therethrough that issignificantly larger may cause permanent deformation (i.e. plasticdeformation or tearing) to seal zone portion 101 s. Thus, according tosome preferred embodiments of the present invention, in which seal zoneportion 101 s has a diameter tailored to accommodate the relativelylarge diameter instruments/devices, exposed sealing area 123 is usefulto prevent excessive leakage/backflow from catheter 100, for example, aswill be described in conjunction with FIGS. 2B-C. However, according toother preferred embodiments, in order to accommodate a larger range ofdiameters, seal zone portion 101 s includes a slit segment 502 thatextends proximally from a distal end of seal zone portion 101 s and intoa bore 515 of seal portion 101 s, for example, as illustrated in FIG. 5Aand described in greater detail below, in conjunction with FIGS. 4A-Band 5A-C.

FIG. 2B is a schematic depicting an operator holding proximal section 11of catheter 100. FIG. 2B illustrates guide wire 200/200′ extendingproximally out from proximal terminal end 113, and a thumb 21 of theoperator being held over proximal opening 31 (FIG. 2A) and pressingguide wire 200/200′ against exposed sealing area 123. Guide wire200/200′ is a steerable instrument, known to those skilled in the art,which is useful for maneuvering within, for example, a venous anatomy ofa patient's body. Relatively large diameter guide wire 200′ may be usedto introduce catheter 100 into the patient's venous system, according tomethods known in the art. Once catheter 100 has been advanced over guidewire 200′, so that distal end 19 (FIG. 2A) is positioned within thevenous system, guide wire 200′ may be exchanged for relatively smalldiameter guide wire 200, whose distal end 209, may be maneuvered outfrom distal end 19 of catheter 100 and into proximity with a targetsite. A therapy-delivering medical device, for example, a medicalelectrical lead, may then be advanced through catheter 100 and overguide wire 200 to the target site. Alternately, another type ofinstrument, such as a steerable electrophysiology (EP) catheter and/or asub-selecting catheter, both known in the art, may be exchanged forlarge diameter guide wire 200′ in order to provide access in closerproximity to the target site, prior to advancing the therapy-deliveringmedical device through catheter 100. In any case, while guide wire200/200′, or another comparably sized instrument, extends withincatheter 100, if seal zone portion 101 s is one that is tailored to sealbest around larger diameter instruments/devices, for example, medicalelectrical leads, the operator can hold his thumb 21 over proximalopening 31 to prevent leakage of blood, and/or other fluids, fromcatheter 100 while the other hand of the operator (not shown) may graspa proximal portion 230 of guide wire 200/200′ to maneuver guide wire200/200′ and catheter 100 relative to one another. With reference toFIG. 2B, it may be appreciated that the tapered profile of proximalterminal end 113 orients proximal opening 31 toward thumb 21 of theoperator's hand that grasps proximal section 11 of catheter 100 so thatthe hand may be in a more comfortable position. Furthermore, accordingto preferred embodiments, exposed sealing area 123 provides a relativelysmooth transition and strain relief for that portion of guide wire 200extending from proximal terminal end 113, when thumb 21 is held asshown. Exposed sealing area 123 may also have a relatively lubricioussurface, so that the operator may push and pull guide wire 200 betweenthumb 21 and area 123 with relative ease.

FIG. 2C is a schematic depicting a standard tapered tip (slip-tipconfiguration) of a syringe 210 inserted into proximal section 11 ofcatheter 100 through proximal opening 31 (FIG. 2A) alongside guide wire200/200′, so, like in FIG. 2B, guide wire 200/200′ is pressed againstexposed sealing area 123. The fit of the tip of syringe 210 alongsideguide wire 200/200′, within proximal opening 31, preferably sealsagainst backflow/leakage while syringe 210 is used to inject fluid intocatheter lumen 101, for example, a saline flush or a radiopaque contrastagent that is useful to visualize anatomy in which catheter 100 andguide wire 200/200′ are being maneuvered, as was described above.According to the illustrated embodiment, when syringe 210 is filled withthe contrast agent, the operator may inject a series of small volumes ofthe agent, or ‘puffs’, while maneuvering guide wire 200/200′ and/orcatheter 100. Furthermore, as described above, exposed sealing area 123preferably provides a smooth transition and strain relief for guide wire200/200′ and may have a relatively lubricious surface to allow theoperator to move guide wire 200/200′ between the tip of syringe 210 andexposed sealing area 123, without significantly compromising the sealinginterface therebetween.

With reference back to FIG. 2A, a relatively soft inner surface 201preferably defines a portion of a perimeter of proximal port portion 101p of lumen 101, just inside proximal opening 31 and extending distallytherefrom; inner surface 201 maybe an integral extension of exposedsealing area 123, as mentioned above and further described below.Relatively soft inner surface 201 may provide additional sealing andstrain relief at the interface between guide wire 200/200′ and theinserted tip of syringe 210. It should be noted that some operators mayprefer to maneuver catheter 100 without any guide wire extendingtherein, in which case, the fit of syringe 210 within proximal opening31, without any guide wire extending therethrough, and with or withoutrelatively soft inner surface 201, also seals against backflow/leakage.

With reference back to the prior art system of FIG. 1, it may beappreciated that syringe 810 coupled to side tubing port 826 of sealingassembly 820, via stopcock 827, is a relatively bulky set up compared tothe inline attachment of syringe 210 with proximal section 11 ofcatheter 100, according to the assembly illustrated in FIG. 2C, and thatthis inline attachment can make the maneuvering of catheter 100, eitherwith or without guide wire 200/200′ extending therein, less cumbersome.According to some embodiments of the present invention, which will bedescribed below, in conjunction with FIGS. 7A-D and 8A-B, a syringeadapter tool may be provided to further facilitate the inline attachmentof a syringe.

FIG. 3A is an exploded perspective view of proximal section 11 ofcatheter 100, according to some embodiments of the present invention.FIG. 3A illustrates relatively rigid sidewall 111 of proximal section 11including two relatively rigid separable parts 111A, 111B, and furtherillustrates exposed sealing area 123 being formed by a relatively softpart 311 that is fixedly attached to part 111A of the two separableparts to form a sealing assembly 30, another perspective view of whichis shown in FIG. 3B. Relatively soft part 311 has a lower durometer thanparts 111A, 111B, which lower durometer may be within the range of 0 to60 on a Shore A scale, or even lower, for example, on the Shore OOscale. It should be noted that the terms ‘soft’ and ‘hard’ (‘hard’ withrespect to surfaces of the relatively rigid parts described herein) areused throughout to indicate relative durometers. FIG. 3A furtherillustrates part 111B of the two relatively rigid separable parts beingin the form of a hub which is coupled to a tubular member 105 ofcatheter 100. With reference back to FIG. 2A, tubular member 105 isshown extending from proximal section 11 to distal end 19 of catheter100, according to some embodiments.

According to the illustrated embodiment, sealing assembly 30 may beformed independently of the remainder of catheter 100, for example, by atwo shot molding process known in the art, wherein a first shot formsrelatively rigid part 111A and a second shot forms relatively soft part311 within and around part 111A. FIG. 3C is an exploded perspective viewof sealing assembly 30, according to some embodiments, in whichrelatively rigid part 111A and relatively soft part 311 are separatedfrom one another. According to some preferred embodiments, an adhesionof soft part 311 to rigid part 111A, as well as some mechanicalinterlocking therebetween, fixedly attaches soft part 311 to rigid part111A. For example, FIG. 3C illustrates female features 317 formed inrelatively rigid part 111A for interlocking with male features 318 ofrelatively soft part 311, according to some embodiments. To furthersecure/attach soft part 311 to rigid part 111A, soft part 311 may alsobe formed with optional bridges, or belts, for example, indicated withdashed lines in FIG. 3C and by reference numeral 31 b in FIGS. 4A and5A. The material forming relatively rigid part 111A may be Pebax® or anyother suitable relatively rigid and biocompatible material known in theart, such as a polyolefin, and the material forming relatively soft part311 may be LSR or TPE. According to a first exemplary embodiment, amaterial forming relatively rigid part 111A is Pebax® 7033 (availablefrom Arkema), and a material forming relatively soft part 311 is CLS2000LSR (available from Momentive); according to a second exemplaryembodiment, a material forming relatively rigid part 111A is 6523Pro-fax polypropylene (available from LyondellBasell Industries), and amaterial forming relatively soft part 311 is either Dynaflex™ G-6703 TPE(available from GLS Corporation), or Medalist® MD-100 TPE (availablefrom Teknor Apex).

FIG. 3B further illustrates the perimeter of proximal opening 31including a first portion 301 and a second portion 302, according tosome preferred embodiments, wherein first portion 301 protrudesproximally from second portion 302, by virtue of the tapered profile ofproximal terminal end 113, and exposed sealing area 123, which formsfirst portion 301, is exposed by virtue of first portion 301 protrudingproximally from second portion 302. With further reference to FIG. 3C,it may be appreciated that, according to the illustrated embodiment, asingle bulk of material, that is relatively soft part 311 (second shot),forms exposed sealing area 123, relatively soft inner surface 201 ofproximal port portion 101 p of lumen 101 and seal zone portion 101 s oflumen 101. Alternatively, separate bulks of material may employed, forexample, a first bulk for exposed sealing area 123 and soft innersurface 201, and a second bulk for seal zone portion 101 s, beingsegregated from one another along the dashed line shown in FIG. 5A.According to these alternate embodiments, the two materials may be thesame or different, each preferably either an LSR or a TPE, for example,as described above.

Sealing assembly 30 may be connected to hub/relatively rigid second part111B of catheter 100 by insertion therein, per arrow I of FIG. 3A. FIGS.3A-C further illustrate external sealing ridges 315 formed in relativelysoft part 311 of assembly 30 and supported by an underlying wall 307 ofrelatively rigid part 111A; sealing ridges 315 are located alongassembly 30 in order to sealingly engage with an inner surface 305 ofhub 111B when connected thereto. The fit of this sealing interfacebetween ridges 315 and inner surface 305 may be sufficient to secureassembly 30 to proximal section 11, however, according to some preferredembodiments, relatively rigid part 111A of assembly 30 includes at leastone aperture 137A within which a corresponding protruding nub 137B ofhub 111B engages to further secure the connection of assembly 30. FIG.2A shows nub 137B engaged within aperture 137A, and, with reference toFIGS. 2A and 3A, sealing assembly 30, after being secured to hub 111B,may be removable therefrom, for example, by lifting a segment 37, whichsurrounds aperture 137A, of relatively rigid part 111A from around nub137B and pulling back on assembly 30, in a direction opposite to arrowI.

FIG. 4A is an end view of catheter 100, looking into lumen 101 (FIG. 2A)at proximal opening 31, and FIG. 4B is a cross-section view throughsection line A-A of FIG. 2A, in order to show opposite ends ofrelatively soft part 311 of sealing assembly 30, according to someembodiments; and FIG. 5A is a longitudinal cross-section view throughsealing assembly 30 within catheter 100, according to some preferredembodiments. With reference to FIGS. 4A-B and 5A, bore 515 incombination with slit segment 502, which is defined by a slit S, make upseal zone portion 101 s of lumen 101. According to the illustratedembodiment, bore 515 includes cylindrical segment 501 and funnel-likesegment 503; and a distal terminal end 510 of bore 515 is proximallyoffset from a distal face 432 of relatively soft part 311. Withreference to FIGS. 4B and 5A, slit S, that defines slit segment 502, canbe seen formed in distal face 432 and extending longitudinally along adepth from distal face 432 in order to intersect with and extend throughfunnel-like segment 503. (One or more additional slits, for example,along the dashed lines in FIG. 4B, may further define slit segment 502,according to alternate embodiments.) It should be noted that cylindricalsegment 501, according to some alternate embodiments, is not included inbore 515, so that bore only includes funnel-like segment 503, whichterminates at distal terminal end 510. Furthermore, with reference toFIGS. 4A and 5A, it may be appreciated that the tapering aspect ofsegment 503 is asymmetrical about a central longitudinal axis 510 ofseal zone portion 101 s, or confined to only a portion of a perimeter ofsegment 503 rather than encompassing an entire perimeter thereof, thusthe term ‘funnel-like’ is used to distinguish from a symmetrical conicalshape typically associated with the term ‘funnel’. However, it should benoted that, according to some alternate embodiments, funnel-like segment503 may have a symmetrical conical shape.

An unexpanded diameter d_(oc) of cylindrical segment 501 may beapproximately 0.01 inch, for example, to seal around devices instrumentshaving an outer diameter of approximately 0.012 inch and larger, and amaximum, proximal unexpanded diameter d_(ofm) of funnel-like segment 503may be approximately 0.05 inch, for example to seal arounddevices/instruments having an outer diameter of approximately 0.045 to0.055 inch and larger. According to some exemplary embodiments, distalterminal end 510 of bore 515 is offset, proximally, from distal face 432by a distance of approximately 0.015 inch; an overall length ofcylindrical segment 501 is between approximately 0.01 inch andapproximately 0.02 inch; an overall length L_(f) of funnel-like segment503 is approximately 0.05 inch; and slit segment 502 extends proximally,into funnel-like segment 503, over a length of approximately 0.025 inch.It should be noted that, according to some alternate embodiments,overall length L_(f) of funnel-like segment 503 can be long enough toreach proximally, closer to proximal opening 31.

The longitudinal extent of slit segment 502, between distal face 432 anddistal terminal end 510 of bore 515, can act like a one-way valve toenhance the sealing function of seal zone portion 101 s, particularlywhen no instrument/device is passed through seal zone portion 101 s orwhen a relatively small diameter instrument/device (smaller thancylindrical segment diameter d_(oc)), for example, guide wire 200/200′,is passed through seal zone portion 101 s; while the extent of slitsegment 502 into funnel-like segment 503 provides additional capacityfor segments 501, 503 to expand, for example, without plasticdeformation or tearing, and thereby accommodate passage of largerdiameter devices/instruments, for example, up to approximately 0.12 inchdiameter, into and/or through seal zone portion 101 s. When catheter 100is inserted within a patient's body, for example, venous system, andwhen no instrument/device, or a relatively small diameterinstrument/device, is inserted through seal zone portion 101 s, aback-pressure within main portion 101 m of catheter lumen 101 exerts aforce against distal face 432 to cause confronting faces of slit S, inproximity to distal face 432, to seal together and thereby prevent all,or most of backflow out through proximal opening 31. A depth of slitsegment 502 in conjunction with a durometer and elongation andcompression properties of the bulk of material, i.e. soft part 311, andan interference fit of soft part 311 within sidewall 111 of catheter100, along the depth of slit segment 502, which provides for somecompressive pre-loading of slit segment 502, are all interrelatedfactors contributing to this sealing integrity. When a relatively largediameter instrument/device is inserted through seal zone portion 101 s,the longitudinal extent of slit segment 502 into funnel-like segment 503facilitates expansion of the smaller diameter portions of funnel-likesegment 503, through which slit segment 502 extends, and of cylindricalsegment 501, around a larger instrument/device inserted therethrough,while the larger diameter portion of funnel-like segment 503, which islocated proximal to a proximal termination of slit segment 502 and whichis smaller than the diameter of the larger diameter instrument/device,seals around a perimeter of the larger diameter instrument/device.Furthermore, funnel-like segment 503 can decrease the force necessary topush a relatively larger instrument/device into the smaller diameterportions of seal zone portion 101 s. FIGS. 5B-D schematically illustratevarious diameter instrument/devices in relation to seal zone portion 101s, according to some embodiments, and will be described below.

Seal zone portion 101 s of lumen 101 is preferably integral within thesingle bulk of material that is relatively soft part 311 of sealingassembly 30, for example, as shown in FIG. 3C, and, according to somepreferred embodiments, an entirety of bore 515 and slit segment 502,which define seal zone portion 101 s, are formed in this bulk ofmaterial, along with relatively soft inner surface 201 of proximal portportion 101 p and exposed sealing area 123. The dashed line of FIG. 5Adesignates a proximal termination, or opening of bore 515, and, aspointed out, above, in conjunction with FIG. 3C, can also indicate adividing line between two separate bulks of material, according to somealternate embodiments, wherein seal zone portion 101 s is formed in thedistalmost of the two separate bulks. In either case, it should be notedthat the incorporation of seal zone portion 101 s within hub/relativelyrigid part 111B of catheter 100 and in relatively close proximity to thejunction of tubular member 105 with hub 111B, makes proximal section 11of catheter 100 more compact, lengthwise, than many prior art systems,such as that illustrated in FIG. 1, in which separate seal/valveassembly 820 can add some significant length to catheter 800. Withreference back to FIG. 2A the proximity of seal zone portion 101 s tothe proximal junction of tubular member 105 is indicated by a distanceX, which may be between approximately 0.25 and 0.5 inch, according tosome embodiments. A profile of catheter in proximity to the proximaljunction of tubular member 105 typically increases and thereby limits adepth of the insertion of catheter 100 into a patient's body; thus, anadvantage of this more compact length, i.e. distance X, is in allowingfor more of a length of an instrument/device, such as a medicalelectrical lead, within catheter 100, to extend into the patient's bodyand reach a more distal target site. It should be noted that a sealmember formed according to any of the embodiments of seal zone portion101 s, which are described herein, although described for inclusion in aproximal portion of a catheter, may alternately be incorporated in othertypes of medical devices/instruments, and, furthermore within a distalportion of various types of medical instruments/devices, according tosome embodiments.

Each of FIGS. 5B-C is a schematic series of radial sections at variousdepths, D1-D5, along seal zone portion 101 s, according to theembodiments described above (FIGS. 4A-B and 5A). The dashed outline ofFIG. 5B represents a perimeter of a relatively small diameterdevice/instrument, while the dashed outline of FIG. 5C represents aperimeter of a relatively large diameter device/instrument. Depth D5 isat a location coinciding with maximum, unexpanded diameter d_(ofm) offunnel-like segment 503; depths D4 and D3 are at locations within anextent of funnel-like segment 503; depth D2 is at a location within anextent of cylindrical segment 501, or at a third location withinfunnel-like segment 503, if no cylindrical segment is included; anddepth D1 is at a location between distal face 432 and the distalterminal end 510 of bore 515. Although, in neither of the FIGS. 5B-C,slit S is shown expanded, it should be understood that, in FIG. 5B, slitS opens at depth D1 to accommodate the illustrated perimeter of therelatively small diameter device/instrument, and, in FIG. 5C, slit Sopens at each of depths D1-D4 to accommodate the illustrated perimeterof the relatively large diameter device.

According to FIG. 5B, sealing takes place at, and around depth D1,between distal face 432 and the distal end of cylindrical segment 501,and is accomplished by the above-described back-pressure that forcesconfronting faces of slit S together around the perimeter of thedevice/instrument. In the absence of back-pressure, or with relativelylow back-pressure, relatively rigid sidewall 111 (FIG. 5A) providessufficient compressive pre-loading to the bulk of material formingrelatively soft part 311 around seal zone portion 101 s to help to holdthe confronting faces of slit S together for sealing. With referenceagain to FIGS. 4A-B, the orientation of slit S, on a plane thatsymmetrically divides part 311, along sealing zone portion 101 s,facilitates preferential pre-loading of the confronting faces of slit Stoward one another. Furthermore, with reference to FIGS. 3A-B and 5A, anouter surface 351 of soft part 311 that corresponds with seal zoneportion 101 s is preferably sized for an interference fit within innersurface 305 of relatively rigid second part/hub 111B, in proximity tothe junction with tubular member 105, where inner surface 305 tapersdown, as best seen in FIG. 5A. The interference fit may be uniform abouta circumference of part 311 along seal zone portion 101 s, or one orboth of inner surface 305 and outer surface 351 may have a profile tomake compressive pre-loading greater in the direction of the confrontingfaces of slit S. According to an exemplary embodiment, the interferencefit is approximately 10% of an outer diameter of part 311, when thematerial forming part is one of the aforementioned CLS2000 LSR,Dynaflex™ G-6703 TPE, and Medalist® MD-100 TPE. Although FIG. 5A showsinner surface 305 of second part/hub 111B is tapering inward, towardlumen main portion 101 m, along a length of the aforementionedinterference fit with part 311, in alternate embodiments, inner surface305 does not taper along this length.

According to FIG. 5C, it may be appreciated that, at depths D1-D3, thespreading apart of slit S, to allow passage of the relatively largediameter instrument/device, can result in a gap that could allow forsome leakage between the perimeter of the instrument/device and thefaces of slit S. However, as the diameter of the funnel-like segment 503increases, from diameter d_(f3) (D3) to diameter d_(f4) (D4), and fromdiameter d_(f4) to diameter d_(ofm) (D5), the gap decreases (D3 to D4)and disappears (D4 to D5) for a more tightly conforming seal interfacearound the perimeter of the larger diameter device/instrument. Forexample, if depth D4 corresponds to a distal termination of slit S anddiameter d_(f4) is approximately equal to 0.03 inch and diameter d_(ofm)has a diameter approximately equal to 0.05 inch, the perimeter offunnel-like segment 503, over the length between D4 and D5, will expandas little as approximately 10% and up to approximately 83% in order toaccommodate passage therethrough of a medical electrical lead having adiameter of approximately 0.055 inch.

FIG. 5D is a schematic side view of seal zone portion 101 s, accordingto some embodiments, for example, as described above (FIGS. 4A-B and5A). Dashed lines in FIG. 5D indicate an instrument/device, which has amid-sized diameter (i.e. between the above-described relatively smalland relatively large diameters), at two positions with respect to slitsegment 502 of the seal zone portion, wherein the two positions areidentified by L1 and L2 at the leading distal end of theinstrument/device. With reference to the first position L1, at which theleading end is inserted into slit segment 502, just past depth D4 at theproximal terminal end of slit segment 502 (indicated with a dottedline), it may be appreciated that, due to the tapering of funnel-likesegment 503, both proximal to, and within slit segment 502, a forcerequired to push the instrument/device through the seal zone portion islower than if the leading end of the instrument/device were to directlyaddress slit segment 502 and a relatively small diameter bore, forexample, corresponding to cylindrical segment 501. Furthermore, due tothe asymmetry of funnel-like segment 503 and the above-described radialoffset of central longitudinal axis 51 from central longitudinal axis 5,as the instrument/device enters slit segment 502, within funnel-likesegment 503, and the leading end approaches position L2, theinstrument/device preferentially opens up one side of the slit segment502 such that the double dashed line, from point p1 to point p2,indicates the proximal-most line of a conforming/“sealing” interfacebetween the inner surface of funnel-like segment 503 and the perimeterof the instrument/device. However, it should be noted that, according toalternate embodiments, wherein segment 503 is formed as a symmetricalfunnel, the proximal-most line of the conforming interface correspondsto a radial section in proximity to point p1 of FIG. 5D.

With reference back to FIG. 5A, a transition zone 513 extends fromproximal port portion 101 p to seal zone portion 101 s, in order to helpguide insertion of a relatively large instrument/device, for example,having a diameter in the range from approximately 0.04 inch toapproximately 0.12 inch (i.e. a medical electrical lead, an EP catheteror a sub-selecting catheter), from proximal port portion 101 p into sealzone portion 101 s of lumen 101, without the need for any special tool,for example, like the prior art tool 822, described in conjunction withFIG. 1. According to the illustrated embodiment, at least a portion of aperimeter of transition zone 513 tapers down along a first slope,distally from a point d_(d) of proximal port portion 101 p, and thentapers further distally, along a second, steeper slope, down to maximumdiameter d_(ofm) of funnel-like segment 503. According to some exemplaryembodiments, a cross-sectional area of proximal port portion 101 p atpoint d_(d) accommodates a diameter of approximately 0.14 inch, and across-sectional area of transition zone 513, at a point d_(i)accommodates a diameter of approximately 0.09 inch; a longitudinaldistance between point d_(d) and point d_(i) is approximately 0.3 inch;and point d_(i) is proximally is offset from maximum diameter d_(ofm) offunnel-like segment 503, which is approximately 0.05 inch, by a distanceof approximately 0.03 inch.

It should be noted that point d_(i) corresponds with a proximal end ofbore 515, such that a an entire perimeter of a distal section oftransition zone 513, which tapers along the second slope, from pointd_(i) to diameter d_(ofm), is surrounded by the relatively soft materialof relatively soft part 311, while only a portion of a perimeter of aproximal section of transition zone 513, which tapers along the firstslope, is surrounded by the relatively soft material, to form a distalextension of relatively soft inner surface 201, which was describedabove in conjunction with FIGS. 2A and 3A-B. A remainder of theperimeter, extending not only along the proximal section of transitionzone 513 but along an entire length of proximal port portion 101 p,opposite relatively soft inner surface 201, is defined by a relativelyhard inner surface 511 of relatively rigid part 111A of sealing assembly30. According to the illustrated embodiment, the location and extent ofrelatively hard inner surface 511 can facilitate removal of catheter 100from around an implanted device body by slitting therethrough, as willbe described in greater detail below.

FIG. 5A further illustrates central longitudinal axis 51 of seal zoneportion 101 s being radially offset from a central longitudinal axis 5of proximal opening 31, according to some embodiments, for example, toalso facilitate removal of catheter 100 from around an implanted devicebody by slitting, for example, with a tool 60 that is shown in FIG. 6.However, with further reference to FIG. 5A, a minimum thickness T ofrelatively soft part 311 of sealing assembly 30, between seal zoneportion 101 s and surrounding rigid sidewall 111, is preferably no lessthan approximately 0.01 inch, to allow for sufficient compressivesealing about an entire perimeter of the instrument/device passedtherethrough.

FIG. 6 is a perspective view of proximal section 11 of catheter 100,along with slitter tool 60, according to some embodiments, wherein tool60 is positioned for insertion, per arrow Y, into proximal opening 31,alongside a body of an implanted medical electrical lead 600. Lead 600is shown including a connector 650, which may be configured according toan industry standard, for example, IS-1, DF-1, IS-4 or DF-4, and mayhave a profile that does not allow catheter 100 to be removed thereover,for example, due to the connector and/or due to an anchoring sleevemounted thereon, which has a profile too large to fit through catheter100. Due to the profile of lead 600, and/or to generally facilitate theremoval of catheter from around lead 600, once lead has been deliveredthrough catheter 100 and a distal tip 690 of lead 600 (FIG. 9) isimplanted at a target site in a body of a patient, slitter tool 60 isused to cut through the sidewall of catheter 100 so that it may bepeeled away from around lead 600 while catheter 100 is withdrawn fromthe body of the patient. Those skilled in the art are familiar withslitter tools similar to tool 60 and with methods for removing cathetersfrom around implanted lead bodies by slitting through sidewalls ofcatheters, so only those details of FIG. 6 that are relevant toembodiments of the present invention will be described.

FIG. 6 illustrates proximal section 11 including an external engagementfeature 66 that is located in proximity to proximal opening 31, forexample, being formed in relatively rigid part 111A of sealing assembly30, which is best seen in FIG. 3B. According to the illustratedembodiment, external engagement feature 66 defines a gap g into which anoperator may direct a leading edge feature 636 of tool 60 for aninterlocking engagement between tool 60 and proximal section 11; whenfeature 636 of tool 60 engages within gap g of feature 66, lead 600 maybe contained in a groove (not shown) that is formed in a lower surfaceof tool 60, below a nose feature 638 thereof, and a blade 610 of tool 60comes into contact with a proximal edge of a relatively thin wallsection 306 of relatively rigid sidewall 111/111A of proximal section11, which spans gap g and may be better seen in FIGS. 3B-C and 4A. Asthe operator begins to slit through wall section 306, feature 636 oftool 60 is constrained within gap g by opposing sides of feature 66.

With further reference to FIG. 4A, in conjunction with FIG. 5A, it maybe appreciated how the aforementioned offset of central longitudinalaxis 51 of seal zone portion 101 s of lumen 101 provides for arelatively thin wall section extending along a length of sealingassembly 30 in order to facilitate the continued slitting with tool 60.Thus, it may be appreciated that, in addition to providing aninterlocking engagement with slitter tool 60, external engagementfeature 66 of catheter proximal section 11 also serves as a visual cuefor the operator to properly orient blade 610 of slitter tool 60 withthe proximal edge of relatively thin wall section 306 in order tocommence slitting along a path that extends through the relatively thinwall section of sealing assembly 30. As mentioned above, relatively hardinner surface 511 defines a portion of the perimeter of proximal portportion 101 p, which portion generally corresponds to second portion 302of proximal opening (FIG. 3B) and extends distally from the proximaledge of relatively thin wall section 306. An extent of relatively hardinner surface 511 maintains a ‘solid’ interface with nose feature 638and, according to some preferred embodiments, for example, asillustrated in FIG. 5A, relatively hard inner surface extends all theway to point d_(i) in order to keep blade 610 on a slitting path thatintersects with slit segment 502 of seal zone portion 101 s; otherwise,if blade 610 were to interface with a relatively soft inner surface, forexample, anywhere along a length of proximal port portion 101 p, theoperator may have a more difficult time in keeping blade 610 fromwandering outward, away from axis 510 before reaching seal zone portion101 s.

With reference back to FIG. 3C, some weakened areas are shown formed inrelatively rigid part 111A in order to further facilitate slitting withtool 60, according to some preferred embodiments. FIG. 3C illustratesrecesses 366, which are located below opposing sides of engagementfeature 66 and which extend longitudinally alongside relatively thinwall section 306, and a pair of longitudinally extending grooves 376,which are formed in wall 307, which wall 307 is a distal extension ofrelatively thin wall section 306. The weakened areas formed by recesses366 and grooves 376 can act as hinge features along either side of thewall section 306/307 that is slit apart by slitter tool 60, for example,to increase the ease of slitting.

FIGS. 4A and 5A further illustrate opposing flat wall sections 46 ofinner surface 511 of relatively rigid part 111A of sealing assembly 30extending within proximal port portion 101 p of lumen 101. According tothe illustrated embodiment, opposing flat wall sections 46 are distallyoffset from proximal opening 31 and are configured to serve as aninternal engagement feature that interfaces with nose feature 638 ofslitter tool 60 to act as a guide. Once blade 610 of tool 60 has slitthrough the proximal edge of relatively thin wall section 306 and, asthe operator continues to pull proximal section 11 of catheter 100proximally against blade 610, the guiding of nose 638 between flat wallsections 46 helps to prevent a lateral wandering of tool 60 and therebymaintain a relatively straight slitting path through catheter proximalsection 11. Of course, various configurations of inner surface 511within proximal port portion 101 p, other than the illustrated flat wallsections 46, can form an internal engagement feature or guide for nose638 of slitter, and are not outside the scope of the present invention.FIG. 6 further illustrates a secondary external engagement feature 67which is formed in hub/relatively rigid second part 111B and locateddistal to external engagement feature 66, being approximately alignedwith feature 66, for example, to help to further stabilize tool 60 asthe operator continues slitting proximal section 11, distal of sealingassembly 30, since feature 636 of tool 60 will be constrained betweenopposing sides of feature 67. With reference back to FIG. 3A, secondaryexternal engagement feature 67 may also serve as a visual cue to helporient sealing assembly 30 for insertion into hub/relatively rigidsecond part 111B of proximal section 11 of catheter 100.

FIG. 7A is a plan view of proximal section 11 of catheter 100 along witha syringe adapter tool 720 and a syringe 710, according to someembodiments. FIG. 7A illustrates adapter tool 720 including a distal tipsegment 721, a proximal attachment segment 727, a feature 725 configuredto interlock with external engagement feature 66 of proximal section 11,and a gripping segment 702 from which feature 725 extends in acantilever fashion. Tool 720 is shown positioned/oriented for theinsertion of distal tip segment 721 into proximal opening 31 of catheterlumen 101 and for the engagement of feature 725 with external engagementfeature 66 of proximal section 11, for example, as illustrated in FIGS.7B-C. Syringe 710 is shown positioned for attachment to tool 720, sothat a tip 717 of syringe 710 can be inserted into a bore 729 ofproximal attachment segment 727, for example, as illustrated in FIGS.7B-C; thus, fluid from syringe can be injected into lumen 101 ofcatheter 100, through a channel 722 of distal tip segment 721, which isin fluid communication with bore 729. The location and configuration ofgripping segment 702, between distal tip segment 721 and proximalattachment segment 727, allows an operator to grasp tool 720 for theaforementioned insertion of distal tip segment 721 into proximal opening31 of catheter lumen 101 and the insertion of syringe tip 717 into bore729 of tool 720.

FIG. 7A further illustrates tool including another feature 723configured to interlock with an internal engagement feature of proximalsection 11, such as opposing flat wall sections 46 (FIGS. 4A, 5A) withinproximal port portion 101 p of lumen 101. With reference to FIG. 7D, itmay be seen that feature 723 includes relatively flat external surfaceslocated on either side of tool 720, each of which surface will face acorresponding flat wall section 46 of the internal engagement feature ofproximal section 11, when interlocked therewith. According to theillustrated embodiment, when features 725 and 723 interlock withrespective external and internal engagement features 66 and 46 ofcatheter proximal end 11, distal tip segment 721 extends within lumen101, to, and, preferably through seal zone portion 101 s, as illustratedin the longitudinal section view of FIG. 7C. An outer diameter of distaltip segment is, thus, preferably sized to fit through seal zone portion101 s, and, according to some embodiments, may be sized for sealingengagement therein. Furthermore, the interlocking of one or both offeatures 725, 723 of tool 720 allows the operator to transfer atorsional force from the attached syringe 710 (FIGS. 7B-C) to catheter100, through tool 720. Such capability gives the operator ability tosimultaneously inject a contrast agent from syringe 710, throughcatheter lumen 101, and to maneuver catheter 100, via applied torque, inorder to position the distal end 19 thereof (FIG. 2A) at a targetlocation in a body of a patient. FIG. 7A further illustrates proximalattachment segment 727 of adapter tool 720 including an external feature728 for mating with a luer lock 718 of syringe tip 717 in order tofurther secure the attachment of syringe 710 to tool 720 for torquetransfer, according to some preferred embodiments.

With further reference to FIG. 7C, guide wire 200 is shown extendingdistally, from proximal portion 230 thereof, through tool 720 and intolumen 101. According to the illustrated embodiment, tool 720 furtherincludes an instrument loading segment 726 to accommodate insertion ofguide wire 200 into catheter 100. However, it should be noted thatalternate embodiments of tool 720 need not include loading segment 726,in which case, guidewire 200 and/or another device/instrument could passthrough seal zone portion 101 s of lumen 101 alongside tool 720. FIG. 7Dis a plan view of syringe adapter tool 720, according to someembodiments, wherein instrument loading segment 726 is shown including apassageway 724, which communicates with channel 722 of distal tipsegment 721 and is accessible from an exterior of tool 720, so thatdistal tip 209 (FIGS. 1 and 9) of guide wire 200 may be inserted intochannel 722, via passageway 724, and through seal zone portion 101 s,via channel 722. An operator may desire to pass guide wire 200 throughcatheter and maneuver distal tip 209 thereof to a target site prior toloading and delivering a medical device, for example, medical electricallead 600 (FIGS. 6 and 9), over guide wire 200. Absent any tool to set upa pathway through seal zone portion 101 s, for example, channel 722, anoperator may have some difficulty passing distal tip 209 of guide wire200 through seal zone portion 101 s, since distal tip 209 is preferablyrelatively floppy (to be atraumatic within the body of the patient) anddeformable (to be shapeable in order to facilitate the steering thereofin the body). An operator may alternately pass a medical device, such aslead 600, through seal zone portion 101 s and into catheter 100, withouttool 720, prior to advancing guide wire 200 into catheter 100, in whichcase a lumen of the medical device provides the passageway through sealzone portion 101 s for guide wire 200. Furthermore, the embodiment oftool 720 that includes loading segment 726 may facilitate insertion ofthe relatively large diameter guide wire 200′, if the operator desiresto insert catheter 100 before, or simultaneously with, the insertion ofguide wire 200′.

FIG. 7D further illustrates distal tip segment 721 having a lengthL_(t), which is, preferably, sufficient to reach through seal zoneportion 101 s, before tool 720 is fully inserted, so that at least aportion of passageway 724 is exposed proximal to proximal terminal end113 of proximal section 11 for the insertion of guide wire distal tip209. Once guide wire 200 has been passed in through passageway 724 andtool 720 is fully inserted, as illustrated in FIG. 7C, passageway 724 ispositioned distal to proximal opening 31 so that exposed sealing area123 can seal over passageway 724 to prevent leakage from lumen 101 ofcatheter 100 and from attached syringe 710, while allowing guide wire200 to extend proximally out from passageway 724 and proximal opening31. As previously described, in conjunction with FIGS. 3A-C and 5A,according to some preferred embodiments, exposed sealing area 123, asformed by soft part 311, extends into proximal port portion 101 p oflumen 101 as relatively soft inner surface 201, which can provideadditional sealing and strain relief at the interface between guide wire200 and tool 720. With reference to FIGS. 7B-C, the location of externalengagement feature 66 of catheter proximal section 11 opposite exposedsealing area 123, and the location of feature 725 of syringe adaptertool 720 opposite passageway 724 assure a proper orientation ofpassageway 724 toward exposed sealing area 123 (and relatively softinner surface 201), for the above-described function, when features 725interlocks with external engagement feature 66. FIG. 7D furtherillustrates tool 720 including an external surface 76 in which anoptional groove 72 is formed; surface 76 and groove 72 are shown locatedjust proximal to passageway 724 to receive that portion of guide wire200 that extends just proximal to exposed sealing area.

With reference to FIGS. 7B-C, when syringe 710 is attached to catheter100, via tool 720, an operator has the ability to inject a contrastagent from syringe 710 through catheter lumen 101 while applying torqueto catheter 100 and/or maneuvering guide wire 200, for example, as wasdescribed above, to a target location. With reference back to the priorart system of FIG. 1, it may be appreciated that syringe 810 coupled toside tubing port 826 of sealing assembly 820, via stopcock 827, is arelatively bulky set up compared to the inline attachment of syringe710, via tool 720, to proximal section 11 of catheter 100, and that thisinline attachment can make the maneuvering of catheter 100, inconjunction with syringe injections, less cumbersome and more effective.Although guide wire 200 is described as the instrument whose insertioninto catheter lumen 101 is facilitated by tool 720, passageway 724 andchannel 722 may be sized to accommodate other types of instruments.

With further reference to FIG. 7D, distal tip segment 721 of syringeadapter tool 720 includes an optional slit 71 extending through asidewall thereof, along length L_(t) and between a distal opening intochannel 722 and passageway 724. According to the illustrated embodiment,slit 71 allows guide wire 200 to pass therethrough, for example, bydeformation of the sidewall of distal tip segment 721, in order toseparate tool 720 from guide wire 200, which remains positioned withincatheter 100 while tool 720 is pulled out from proximal section 11 ofcatheter 100. It should be noted that, tool 720 is preferably designedto be reusable, having relatively robust wall sections that will notpermanently deform under repeated use, for example, during a procedurein which the operator needs to employ several guide wires in successionin order to reach the target site. According to an exemplary embodiment,tool 720 is formed from a polyether block amide such as Pebax®, or apolyolefin, such as Pro-fax polypropylene.

FIG. 8A is a perspective view of a syringe adapter tool 920, accordingto some alternate embodiments. FIG. 8A illustrates tool 920 having aconfiguration similar to tool 720, for example, in that tool 920includes distal tip segment 721, gripping segment 702, proximalattachment segment 727, feature 725 configured to interlock withexternal engagement feature 66 of proximal section 11, and feature 723configured to interlock with the internal engagement feature of catheterproximal section 11 (i.e. opposing flat wall sections 46). FIG. 8A alsoshows tool 920 including optional instrument loading segment 726 withpassageway 724 for insertion of an instrument, such as guide wire 200,into channel 722 of distal tip segment 721, as described above for tool720. Like adapter tool 720, adapter tool 920 is preferably designed tobe reusable. In contrast to tool 720, tool 920 includes a sealing member93, for example, formed from a relatively soft material, such as an LSRor a TPE, which may be over-molded onto a relatively rigid part 97 oftool 920, as will be described in greater detail below. FIG. 8Aillustrates sealing member 93 extending distally from gripping segment702 and including a sealing ring 934 and a lip 936.

FIG. 8B is an enlarged perspective view of tool 920 engaged withcatheter proximal section 11 and syringe 710 attached to tool 920. Withreference to FIGS. 8A-B, in conjunction with FIG. 7C, it may beappreciated that sealing ring 934 is positioned on tool 920 at alocation for sealing within proximal port portion 101 p of lumen 101,just distal to proximal opening 31, when tool 920 interlocks withcatheter proximal section 11. FIG. 8B illustrates lip 936 abuttingproximal terminal end 113 of catheter proximal section 11 along exposedsealing area 123, for example, to provide additional protection againstbackflow out from proximal opening 31 of lumen 101. FIGS. 8A-B furtherillustrate an optional groove 92 formed in sealing member 93 andextending longitudinally through ring 934 and lip 936 in order to betteraccommodate a proximal extension of an instrument, such as guide wire200, that passes between sealing member 93 and exposed sealing area 123.However, it should be noted that the interface between theabove-described relatively soft inner surface 201 of proximal portportion 101 p and the relatively soft material (for example, one of theaforementioned CLS2000 LSR, Dynaflex™ G-6703 TPE, and Medalist® MD-100TPE) that forms sealing member 93, at and around ring 934, can conformaround the interposed instrument/guide wire so that groove 92 may not benecessary.

With further reference to FIG. 8A, tool 920 is shown divided into tworelatively rigid parts 95 and 97, according to some preferredembodiments. FIG. 8A shows first part 95 forming a first portion ofgripping segment 702 and feature 725, and shows second part 97 formingdistal tip segment 721, optional loading segment 726, a second portionof gripping segment 702 and proximal attachment segment 727. Accordingto some embodiments, sealing member 93 is over-molded onto secondrelatively rigid part 97 before attaching first relatively rigid part 95to second part 97, for example, since the cantilever extension offeature 725 can interfere with such a molding operation. Part 97 may beformed from a polyether block amide such as Pebax®, or a polyolefin suchas Pro-fax, while part 95 may be formed from an even more rigidmaterial, for example, a polycarbonate, such as Makrolon 4258 (availablefrom Bayer), or a co-polyester, such as Tritan MX731 (available fromEastman), for example, to strengthen feature 725 against deformationwhen feature 725 interlocks with external engagement feature 66 ofcatheter proximal section 11 and torsional forces are applied to tool920. According to a first exemplary embodiment, part 97 is formed byPebax® 7033 (available from Arkema) and sealing member 93 is formed byCLS2000 LSR (available from Momentive); and, according to a secondexemplary embodiment, part 97 is formed by 6523 Pro-fax polypropylene(available from LyondellBasell Industries) and sealing member 93 isformed by either Dynaflex™ G-6703 TPE (available from GLS Corporation),or Medalist® MD-100 TPE (available from Teknor Apex).

Finally, FIG. 9 is a plan view of a delivery system, wherein lead 600 isshown inserted within catheter 100. FIG. 9 illustrates the systemincluding catheter 100, relatively smaller diameter guide wire 200,relatively larger diameter guide wire 200′, syringe 710, syringe adaptertool 720/920 and slitter tool 60, for example, as have been describedabove. Although not shown, the system may further include one or moreadditional related accessories known in the art, which include, withoutlimitation, additional guide wires, a dilator and a sub-selectingcatheter. With reference to a sub-selecting catheter, it should be notedthat such a catheter may have a proximal section including any or all ofthe features described above for proximal section 11, but that thesub-selecting catheter would necessarily include a smaller diametertubular member (corresponding to tubular member 105 of catheter 100) inorder to fit within catheter lumen 101. Catheter 100 and one or two ofsyringe adapter tool 720/920 may be packaged as a kit, which may alsoinclude any combination of one or more of the other related accessoriesmentioned above.

According to some methods of the present invention, an operator attachessyringe 710 to adapter tool 720/920 and inserts distal tip segment 721of tool 720/920 into proximal opening 31 of catheter 100, for example,as illustrated in FIGS. 7B and 8B, and then purges catheter 100 of anyair by flushing saline through lumen 101, prior to inserting catheter100 into a body, for example, the venous system of a patient. Aspreviously described, catheter 100 may be inserted over a pre-positionedrelatively large diameter guide wire 200′. Once catheter 100 is insertedinto the patient, the operator maneuvers catheter 100, by pushing andapplying torque to proximal section 11, such that distal end 19 thereofis positioned, for example, in proximity to, or within the ostium of thepatient's coronary sinus (CS Os). With reference back to FIGS. 7A-C and8B, it may be appreciated that, according to preferred methods, theoperator aligns feature 725 of tool 720/920 with external engagementfeature 66 of catheter proximal section 11 in order to interlock feature725 with feature 66, as distal tip segment 721 of tool 720/920 is beinginserted through proximal opening 31 and into seal zone portion 101 s ofcatheter lumen 101. According to the illustrated embodiment, feature 723of tool 720/920 also interlocks with internal engagement feature 46 ofcatheter proximal section 11 (FIGS. 4A and 5A), upon insertion throughproximal opening 31. The inline and interlocking attachment of syringe710, via tool 720/920, with catheter proximal section 11, allows theoperator to grasp the attached syringe 710 in order to maneuver catheter100. Once distal end 19 of catheter 100 is positioned in generalproximity to the CS Os, within the patient's right atrium, for example,being confirmed by fluoroscopic visualization of a radiopaque markerattached to catheter distal end 19, the operator may inject a radiopaquecontrast agent from syringe 710, in order to better locate/visualize theCS Os, according to methods known in the art, while maneuvering catheter100 to canulate the CS Os with catheter distal end 19, for example, byapplying push and torque forces to catheter proximal section 11 whilegrasping syringe 710. It should be noted that a similar method may beused to position distal end 19 of catheter 100 in proximity to a targetlocation along a wall of the atrium or along a right ventricular wall,for example, for subsequent site specific delivery of a medicalinstrument to the target location.

Once distal end 19 of catheter 100 is positioned, for example, withinthe CS Os, the operator may deliver lead 600 through catheter, eitherindependent of guide wire 200, along with guide wire 200, which has beenpre-loaded into lead 600, or over guide wire 200, so that distal tip 690of lead 600, which may include one or more electrodes for electricalstimulation of the target site, is positioned distal to distal end 19 ofcatheter 100, as illustrated in FIG. 9. If lead 600 is to be deliveredover guide wire 200, guide wire 200 may be inserted through seal zoneportion 101 s of lumen 101, with the aid of adapter tool 720/920, whenadapter tool 720/920 includes loading segment 726. According to somemethods, tool 720/920 is withdrawn just enough so that passageway 724 isexposed just proximal to catheter proximal opening 31 for the insertionof guide wire distal tip 209 therein and through channel 722 of distaltip segment 721, to pass through seal zone portion 101 s of catheterlumen 101. Once catheter 100 and guide wire 200 are assembled together,for example, as illustrated in FIG. 7C, contrast agent may be injectedfrom the attached syringe 710 while wire is maneuvered independently ofcatheter 100 and/or together with catheter 100, which operation may befacilitated by the inline and interlocking engagement of syringe 710 viatool 720/920. Once guide wire tip 209 is positioned, lead 600 may beloaded over proximal portion 230 of guide wire 200, for deliverythereover, after adapter tool 720/920 is completely withdrawn fromcatheter proximal section 11, as previously described, by passingproximal portion 230 of guide wire 200 through slit 71 in the sidewallof distal tip segment 721. Alternately, guide wire 200 may be loadedinto lead 600, either before or after lead 600 is passed into catheter100, through seal zone portion 101 s, in which case, lead 600 itselffacilitates passage of guide wire distal tip 209 through seal zoneportion 101 s. With reference back to FIGS. 4A and 5A and thedescription associated therewith, it may be appreciated that transitionzone 513 facilitates the insertion of a relatively largeinstrument/device, for example, such as lead 600, through seal zoneportion 101 s of catheter lumen 101, without the need for a specialinsertion tool. As is also described above, once lead 600 is implanted,catheter 100 may be removed from around lead 600 by slitting, forexample, with slitter tool 60.

In the foregoing detailed description of the disclosure, specificexemplary embodiments of the invention have been described. However, itmay be appreciated that various modifications and changes can be made,without departing from the scope of the disclosure, as set forth in theappended claims.

We claim:
 1. A sealing assembly for a catheter comprising: a lumenproviding passage into a main lumen of the catheter when the sealingassembly is connected to the catheter, the lumen of the sealing assemblyincluding a proximal opening, a proximal port portion and a seal zoneportion, the proximal port portion extending from the proximal openingdistally to the seal zone portion; a proximal terminal end having atapered profile and defining a perimeter of the proximal opening of thelumen of the sealing assembly, the proximal terminal end including anexposed sealing area, and the perimeter of the proximal openingincluding a first portion and a second portion, the first portionprotruding proximally from the second portion by virtue of the taperedprofile of the proximal terminal end; a relatively rigid part includingan attachment feature for removably connecting the sealing assembly to ahub of the catheter; and a relatively soft part forming at least theseal zone portion of the lumen of the sealing assembly and the exposedsealing area of the proximal terminal end; wherein the exposed sealingarea forms the first portion of the perimeter of proximal opening of thelumen of the sealing assembly and is exposed by virtue of the firstportion of the perimeter of the proximal opening protruding proximallyfrom the second portion of the perimeter.
 2. The sealing assembly ofclaim 1, wherein the proximal opening and the proximal port portion ofthe lumen of the sealing assembly is sized to receive insertion thereinof a standard tapered tip of a syringe.
 3. The sealing assembly of claim1, wherein the seal zone portion of the lumen of the sealing assemblyincludes a funnel-like segment and a slit segment, the funnel-likesegment tapering down in size from a proximal diameter thereof to adistal diameter thereof, and the slit segment extending proximally fromthe main lumen of the catheter, when the sealing assembly is connectedto the catheter, to intersect with the funnel-like segment.
 4. Thesealing assembly of claim 3, wherein the seal zone portion of the lumenof the sealing assembly further includes a cylindrical segment having adistal terminal end and extending between the distal diameter of thefunnel-like segment and the distal terminal end, the distal terminal endof the cylindrical segment being offset proximally from the main lumenof the catheter, when the sealing assembly is connected to the catheter.5. The sealing assembly of claim 3, wherein: the distal diameter of thefunnel-like segment of the seal zone portion of the lumen of the sealingassembly is approximately 0.01 inch; the proximal diameter of thefunnel-like segment of the seal zone portion of the lumen of the sealingassembly is approximately 0.05 inch; and a length of the funnel-likesegment, from the proximal diameter to the distal diameter, isapproximately 0.05 inch.
 6. The sealing assembly of claim 3, wherein thelumen of the sealing assembly further includes a transition zoneextending from the proximal port portion of the lumen to the funnel-likesegment of the seal zone portion of the lumen, the transition zonetapering down from the proximal port portion to the proximal diameter ofthe funnel-like segment.
 7. The sealing assembly of claim 6, wherein atleast a portion of a perimeter of the transition zone of the lumen ofthe sealing assembly tapers down along a first slope, distally from theproximal port portion, and then along a second slope, distally from thefirst slope to the proximal diameter of the funnel-like segment, thesecond slope being steeper than the first slope.
 8. The sealing assemblyof claim 6, wherein the relatively rigid part further includes arelatively hard inner surface forming a portion of a perimeter of thetransition zone.
 9. The sealing assembly of claim 1, wherein a centrallongitudinal axis of the seal zone portion of the lumen of the sealingassembly is radially offset from a central longitudinal axis of theproximal opening of the lumen.
 10. The sealing assembly of claim 1,wherein the relatively soft part includes an external sealing ridge thatengages with an internal surface of the hub of the catheter, when theassembly is connected to the hub of the catheter.
 11. The sealingassembly of claim 10, wherein the relatively rigid part underlies andsupports the external sealing ridge.
 12. The sealing assembly of claim1, wherein the attachment feature of the relatively rigid part comprisesan aperture for engaging with a protruding nub of the hub of thecatheter.
 13. The sealing assembly of claim 1, wherein the relativelyrigid part further includes an engagement feature formed therein forinterlocking engagement with a feature of an accessory tool.
 14. Thesealing assembly of claim 1, wherein the relatively rigid part forms thesecond portion of the perimeter of the proximal opening of the lumen ofthe sealing assembly.